文献类型：期刊文献

英文题名：Enhanced durability of propylene epoxidation via La-passivation of Rh sites in Au-Rh/TS-1 catalysts

作者：Hong, Changzheng[1];Zhong, Yuxia[1];Chen, Wenyao[1];Zhang, Zhongyao[1];Zhang, Zhihua[1];Zhang, Jing[1];Qian, Gang[1];Zhou, Xinggui[1];Chen, De[1,2];Duan, Xuezhi[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn & Low Carbon Technol, Shanghai 200237, Peoples R China;[2]Norwegian Univ Sci & Technol, Dept Chem Engn, N-7491 Trondheim, Norway

年份：2026

卷号：330

外文期刊名：CHEMICAL ENGINEERING SCIENCE

收录：;EI(收录号：20261420444141);WOS:【SCI-EXPANDED(收录号:WOS:001737416500001)】；

基金：This work was financially supported by the National Key R & D Program of China (2024YFA1510303) , the Natural Science Foundation of China (22478107, 22038003, 22178100, 22178101, 22208093, and U22B20141) , the Shanghai Pilot Program for Basic Research (22TQ1400100-15) , the Shanghai Rising-Star Program (24QA2701900) , the Innovation Program of Shanghai Municipal Education Commission, and the Shanghai Science and Technology Innovation Action Plan (22JC1403800) .

语种：英文

外文关键词：Direct propylene epoxidation; La-modification; Au-Rh/TS-1; Durability; Coke

摘要：The direct gas-phase epoxidation of propylene with H2 and O2 represents a key green process for producing propylene oxide (PO), yet its industrial application is hindered by the poor long-term stability of Au-Rh/TS-1 catalysts. This study demonstrates that lanthanum (La) modification significantly enhances both the stability and selectivity of the catalyst. Although the introduction of La leads to a slight decrease in initial activity, the modified catalyst exhibits exceptional operational stability, maintaining nearly constant performance over 100 h. More importantly, PO selectivity steadily increased to 70-80% in the presence of La. This profound enhancement stems from La deeply modulating the reaction microenvironment through the synergistic effects of kinetic regulation and spatial restriction. Kinetically, La species weaken the strong adsorption of PO on Ti sites, effectively mitigating product inhibition and restricting the continuous formation of oxygenated soft coke precursors. Spatially, La species dynamically migrated and enriched in the immediate vicinity of the Au-Rh nanoparticles during the reaction, guiding the unavoidable carbon deposits to preferentially accumulate on Rh-rich regions. This site-selective coke layer acted as a functional passivation, precisely blocking Rh sites responsible for side reactions while largely preserving the active Au sites for epoxidation. Furthermore, the oxygenated soft coke can be facilely removed via simple calcination, allowing the catalyst to fully recover its intrinsic performance. This work not only offers an effective La-modification strategy for designing highly stable and selective oxidation catalysts, but also sheds new light on harnessing reaction-driven surface evolution to dynamically optimize catalyst performance.